Sandstone is a type of rock which contains a lot of sand. It is often used for building houses and walls.
...the reddish sandstone walls.
...sandstone cliffs.
sandstone in British English
(ˈsændˌstəʊn)
noun
any of a group of common sedimentary rocks consisting of sand grains consolidated with such materials as quartz, haematite, and clay minerals: used widely in building
sandstone in American English
(ˈsændˌstoʊn)
noun
a common bedded sedimentary rock much used for building, composed largely of sand grains, mainly quartz, held together by silica, lime, etc.